A direct linear relationship was established between hepatic cell volume, based on DNA, and cellular protein and enzymatic activities. In control animals age results in small cells and therefore less protein and enzymatic activities per cell size. Dietary manipulation minimizes these age effects but also results in small cells in all age groups. In addition it was found that the biochemical characteristics of animals depend upon the dietary manipulations to which they are exposed. In order to determine whether the development of specific diseases may be influenced differentially by dietary manipulations genetically determined diabetic mice were studied. With approximately 40% mortality in the diabetic animals fed 24% protein ad libitum, those fed ad libitum a 24% protein diet diluted 50% with cellulose experienced 100% mortality; the intermittent fed animals, 30% mortality; while the low protein (4%) ad libitum fed animals, had no mortality. In addition, observations indicate that all of the 24% protein ad libitum fed animals have polyuria while there is considerably less polyuria in the intermittent animals and thus far no polyuria in the 4% protein ad libitum fed animals. Thus these preliminary findings indicate beneficial effects due to dietary manipulation especially among animals fed the low protein diet which contains approximately 50% more sucrose than the 24% protein diet.